Field
Embodiments of the invention relate to electronic circuits, and more particularly, to voltage variable attenuators.
Description of the Related Technology
A voltage variable attenuator (VVA) can be used in radio frequency (RF) applications to provide a controlled amount of attenuation to signals. The amount of attenuation, or ratio of output signal power level to input signal power level, can be adjusted by an analog attenuation control signal, such as an attenuation control voltage. In certain implementations, the attenuation control voltage is set via a feedback loop.
In one application, a VVA is used in a transceiver to adjust the signal strength of an RF signal that is amplified by a power amplifier. Thus, a VVA can be used to control a transceiver's transmit power. In another application, a VVA is used in a transceiver to provide attenuation to the output of a low noise amplifier (LNA), and the VVA's attenuation is controlled via feedback to regulate the power level of a received signal.